BACKGROUND: Parental psychopathology may increase the risk of attention-deficit hyperactivity disorder (ADHD) in the offspring. The aim of this study was to analyze if/how gender influences the association between parental psychiatric/addictive disorders and ADHD medication in the offspring.

METHODS: Register study in national birth cohorts of 1.1 million 6-19-year-olds. In this population, 7960 individuals with ADHD medication were identified in the Swedish Prescribed Drug Register during 2006. Data on parental psychiatric/addictive disorders and suicide death were obtained through linkages to national registers. Logistic regression was used for analyses with multiple adjustments for socio-economic, regional and demographic confounders.

RESULTS: Parental diagnosis related to illicit drugs was associated with the highest odds ratios (ORs) of ADHD medication (OR: -3.5-4), followed by suicide attempt/death (OR: -3-3.5), alcohol (OR: -2.5-3), affective disorder (OR: -2.5) and psychosis (OR: -2-2.5). The ORs were of similar magnitudes for maternal and paternal psychopathology and did not vary by the gender of the offspring. Adjusting for social characteristics decreased the ORs substantially and in the same way regarding fathers' and mothers' possible influence on the risk of ADHD in children.

CONCLUSIONS: Neither parental nor offspring gender seems to influence the link between parental addictive/psychiatric disorder and offspring ADHD.